When the diesel engines operate under light loads, the cylinder pressure is too low under the lightly loaded conditions for the piston rings to form a good seal and keep the oil out of the cylinders. The oil is discharged from the cylinders with the products of combustion. Without a good seal at the joints in the exhaust manifold system this slobbering oil will drip on the engine and it is difficult to determine the origin of the oil. Whether it is the oil slobber leaking from the exhaust manifold or oil leaking from other oil lines. U.S. Pat. No. 5,414,993 describes a liner in the exhaust port to insulate the exhaust gases from the cylinder head and a gasket placed between the flange of the exhaust manifold and the cylinder head.